that tutorial looks like a real ball ache,
You are joking! A little fiddly, and requiring a little patience and dexterity of the fingers - but that is a job that you could probably do in your lunch break (providing you had the correct tools

). Put it another way - if you can change a battery on a dinky ladies watch, then you could do that job too!
though looks easier than installing an S3 intercooler
Yup - to the meek, the S3 i/c looks like major surgery - but if you have ever worked on something like a Cummins V903 14.7 litre V8 'big-cam' (with the original camshaft operated "unit injector", long before VW invented the PD TDIs) - then nothing really phases you!
